Download or read book Thermal Deposition Analysis During Disruptions on DIII D Using Infrared Scanners written by and published by . This book was released on 1995 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: The DIII-D tokamak generates plasma discharges with currents up to 3 MA and auxiliary input power up to 20 MW from neutral beams and 4 MW from radio frequency systems. In a disruption, a rapid loss of the plasma current and internal thermal energy occurs and the energy is deposited onto the torus graphite wall. Quantifying the spatial and temporal characteristics of the heat deposition is important for engineering and physics-related issues, particularly for designing future machines such as ITER. Using infrared scanners with a time resolution of 120 [mu]s, measurements of the heat deposition onto the all-graphite walls of DIII-D during two types of disruptions have been made. Each scanner contains a single point detector sensitive to 8--12 [mu]m radiation, allowing surface temperatures from 20 C to 2,000 C to be measured. A zinc selenide window that transmits in the infrared is used as the vacuum window. Views of the upper and lower divertor regions and the centerpost provide good coverage of the first wall for single and double null divertor discharges. During disruptions, the thermal energy is not deposited evenly onto the inner surface of the tokamak, but is deposited primarily in the divertor region when operating diverted discharges. Analysis of the heat deposition during a radiative collapse disruption of a 1.5 MA discharge revealed power densities of 300--350 MW/m2 in the divertor region. During the thermal quench of the disruption, the energy deposited onto the divertor region was more than 70% of the stored thermal energy in the discharge prior to the disruption. The spatial distribution and temporal behavior of power deposition during high [beta] disruptions will also be presented.
Download or read book 16th IEEE NPSS Symposium Fusion Engineering written by and published by . This book was released on 1995 with total page 866 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Magnetic and Thermal Energy Flow During Disruptions in DIII D written by and published by . This book was released on 1996 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors present results from disruption experiments where they measure magnetic energy flow across a closed surface surrounding the plasma using a Poynting flux analysis to measure the electromagnetic power, bolometers to measure radiation power and IR scanners to measure radiation and particle heat conduction to the divertor. The initial and final stored energies within the volume are found using the full equilibrium reconstruction code EFIT. From this analysis they calculate an energy balance and find that they can account for all energy deposited on the first wall and the divertor to within about 10%.
Download or read book Fusion Energy 1996 written by International Atomic Energy Agency and published by Fusion Energy 1996. This book was released on 1997 with total page 956 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the Sixteenth International Conference, formerly called the International Conference on Plasma Physics and Controlled Nuclear Fusion Research, Montreal, 7-11 October 1996. The papers presented reflect the excellent progress achieved since the last conference in Seville 1994. Among many other achievements, the Tokamak Fusion Test Reactor has produced over 10 MW of fusion power, the JT-60U experiment has demonstrated plasma conditions equivalent to breakeven, the reversed shear mode has been demonstrated, low aspect ratio tokamaks have produced promising results and plans have been drawn up for powerful new inertial confinement fusion experiments.
Download or read book DIII D Disruption Experiment Results written by and published by . This book was released on 1995 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tokamak discharges are frequently ended by disruptions, an instability leading to a very sudden termination of the plasma. Although numerous studies of disruptions have been made, critical data is still needed to develop theoretical models for fundamental aspects of the disruption. This paper describes simultaneous profile measurements of the current, temperature, and density during the disruptive phase of a beam heated single-null divertor discharge in the DIII-D tokamak. The stored energy is lost early in the first phase of the disruption (thermal quench) after which the central temperature is a few hundred eV, and following the start of the current decay (current quench) the temperature has fallen to 100 eV. The current profile measured using the Motional Stark Effect (MSE) diagnostic is observed to flatten rapidly (
Download or read book Index to IEEE Publications written by Institute of Electrical and Electronics Engineers and published by . This book was released on 1996 with total page 1208 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues for 1973- cover the entire IEEE technical literature.
Download or read book Radiation Asymmetries During Disruptions on DIII D Caused by Massive Gas Injection written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the major challenges that the ITER tokamak will have to face during its operations are disruptions. During the last few years, it has been proven that the global consequences of a disruption can be mitigated by the injection of large quantities of impurities. But one aspect that has been difficult to study was the possibility of local effects inside the torus during such injection that could damage a portion of the device despite the global heat losses and generated currents remaining below design parameter. 3D MHD simulations show that there is a potential for large toroidal asymmetries of the radiated power during impurity injection due to the interaction between the particle injection plume and a large n=1 mode. Another aspect of 3D effects is the potential occurrence of Vertical Displacement Events (VDE), which could induce large poloidal heat load asymmetries. This potential deleterious effect of 3D phenomena has been studied on the DIII-D tokamak thanks to the implementation of a multi-location massive gas injection (MGI) system as well as new diagnostic capabilities. This study showed the existence of a correlation between the location of the n=1 mode and the local heat load on the plasma facing components but shows also that this effect is much smaller than anticipated (peaking factor of ~1.1 vs 3-4 according to the simulations). There seems to be no observable heat load on the first wall of DIII-D at the location of the impurity injection port as well as no significant radiation asymmetries whether one or 2 valves are fired. This study enabled the first attempt of mitigation of a VDE using impurity injection at different poloidal locations. The results showed a more favorable heat deposition when the VDE is mitigated early (right at the onset) by impurity injection. As a result, no significant improvement of the heat load mitigation efficiency has been observed for late particle injection whether the injection is done "in the way" of the VDE (upward VDE mitigated by injection from the upper part of the vessel vs the lower part) or not.
Download or read book Physics Briefs written by and published by . This book was released on 1993 with total page 1116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sur l tat physique des constituants cellulaires written by Louis Lapicque and published by . This book was released on 1929 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 772 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fusion Energy Update written by and published by . This book was released on 1986 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thermal Analysis written by T. Hatakeyama and published by John Wiley & Sons. This book was released on 1999-05-04 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermal Analysis Fundamentals and Applications to Polymer Science T. Hatakeyama Otsuma Women's University, Tokyo, Japan F. X. Quinn L'Oréal Recherche Advancée, Aulnay-sous-Bois, France The first edition of this classic book remains one of the very few introductory books covering both theoretical and practical aspects of thermal analysis (TA). This new edition includes a much enlarged section on MDSC, in which the instrument is described and a critical appraisal of the technique presented. Other additions include new sections on rate-controlled TGA, OTTER, and Specific Heat Spectroscopy, and a thoroughly updated section on X-Ray DSC. This very practical book is a must for people who use thermal analysis techniques in their everyday work. "An excellent introductory text" - Review of 1st Edition.
Download or read book Magnetic Fusion Technology written by Thomas J. Dolan and published by Springer Science & Business Media. This book was released on 2014-02-10 with total page 816 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetic Fusion Technology describes the technologies that are required for successful development of nuclear fusion power plants using strong magnetic fields. These technologies include: • magnet systems, • plasma heating systems, • control systems, • energy conversion systems, • advanced materials development, • vacuum systems, • cryogenic systems, • plasma diagnostics, • safety systems, and • power plant design studies. Magnetic Fusion Technology will be useful to students and to specialists working in energy research.
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1996 with total page 556 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Columbia Crew Survival Investigation Report written by Nasa and published by PDQ Press. This book was released on 2009 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: NASA commissioned the Columbia Accident Investigation Board (CAIB) to conduct a thorough review of both the technical and the organizational causes of the loss of the Space Shuttle Columbia and her crew on February 1, 2003. The accident investigation that followed determined that a large piece of insulating foam from Columbia's external tank (ET) had come off during ascent and struck the leading edge of the left wing, causing critical damage. The damage was undetected during the mission. The Columbia accident was not survivable. After the Columbia Accident Investigation Board (CAIB) investigation regarding the cause of the accident was completed, further consideration produced the question of whether there were lessons to be learned about how to improve crew survival in the future. This investigation was performed with the belief that a comprehensive, respectful investigation could provide knowledge that can protect future crews in the worldwide community of human space flight. Additionally, in the course of the investigation, several areas of research were identified that could improve our understanding of both nominal space flight and future spacecraft accidents. This report is the first comprehensive, publicly available accident investigation report addressing crew survival for a human spacecraft mishap, and it provides key information for future crew survival investigations. The results of this investigation are intended to add meaning to the sacrifice of the crew's lives by making space flight safer for all future generations.
Download or read book Introduction to Information Retrieval written by Christopher D. Manning and published by Cambridge University Press. This book was released on 2008-07-07 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Class-tested and coherent, this textbook teaches classical and web information retrieval, including web search and the related areas of text classification and text clustering from basic concepts. It gives an up-to-date treatment of all aspects of the design and implementation of systems for gathering, indexing, and searching documents; methods for evaluating systems; and an introduction to the use of machine learning methods on text collections. All the important ideas are explained using examples and figures, making it perfect for introductory courses in information retrieval for advanced undergraduates and graduate students in computer science. Based on feedback from extensive classroom experience, the book has been carefully structured in order to make teaching more natural and effective. Slides and additional exercises (with solutions for lecturers) are also available through the book's supporting website to help course instructors prepare their lectures.
Download or read book Thriving on Our Changing Planet A Decadal Strategy for Earth Observation from Space written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2019-06-18 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: We live on a dynamic Earth shaped by both natural processes and the impacts of humans on their environment. It is in our collective interest to observe and understand our planet, and to predict future behavior to the extent possible, in order to effectively manage resources, successfully respond to threats from natural and human-induced environmental change, and capitalize on the opportunities â€" social, economic, security, and more â€" that such knowledge can bring. By continuously monitoring and exploring Earth, developing a deep understanding of its evolving behavior, and characterizing the processes that shape and reshape the environment in which we live, we not only advance knowledge and basic discovery about our planet, but we further develop the foundation upon which benefits to society are built. Thriving on Our Changing Planet: A Decadal Strategy for Earth Observation from Space (National Academies Press, 2018) provides detailed guidance on how relevant federal agencies can ensure that the United States receives the maximum benefit from its investments in Earth observations from space, while operating within realistic cost constraints. This short booklet, designed to be accessible to the general public, provides a summary of the key ideas and recommendations from the full decadal survey report.
